Adjustable device for motor vehicle seat

ABSTRACT

Disclosed is an adjustment device for a motor vehicle seat having an adjusting element adjustably disposed in its longitudinal direction and in the area of one end, connectable in an articulated manner to a vehicle seat structure, and a drive unit driving the adjusting element. In order to provide an adjustment device of the initially named type, that can be disposed at a vehicle seat component in a simple and reliable manner, it is provided that the drive unit comprises means for the articulated, particularly pivotal, connection to a vehicle seat component, particularly a side member of a seat base frame.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to an adjustment device for a motor vehicle seat,having

-   -   an adjusting element disposed adjustably in its longitudinal        direction and in the area of one end connectable in an        articulated manner to a vehicle seat structure, and    -   a drive unit driving the adjusting element.

2. Description of Related Art

Adjustment devices of the generic type on motor vehicle seats enableeasy adaptation of the seating position to the individual requirementsof the respective user, in that they make the adjustment of thedifferent adjustable seat structures possible, for instance, a seatingsurface or a seatback with respect to a vehicle floor. By means of anadjustment device connected to a seating surface, the option exists toadapt the height of the seating surface and also possibly itsinclination, for example.

To allow an adjustment of the position of the vehicle seat structure bymeans of the adjustment device, it is necessary to position theadjustment device so that a displacement of the adjusting element of theadjustment device in its longitudinal direction created by the driveunit results in a displacement of the vehicle seat structure connectedto the adjusting element. For this purpose, the adjustment device ispreferably disposed at the motor vehicle seat itself, for example at avehicle seat component, preferably at the seat base frame, for exampleat a side surface, in order to guarantee sufficient support for theadjusting element. The arrangement of the adjustment device in anarticulated, particularly in a pivoting manner necessary for atrouble-free operation, often proved to be very complicated because highdemands are placed on the fastening of the adjustment device fortrouble-free and particularly noise-free operation.

BRIEF SUMMARY OF THE INVENTION

The object of the invention is to provide an adjustment device of theinitially named type that can be disposed on a vehicle seat component ina simple and reliable manner. The object of the invention is further toprovide a motor vehicle seat having an adjustment device that is easy toinstall and is highly reliable.

The object is solved by the invention by an adjustment device having thefeatures of claim 1 and by a motor vehicle seat having the features ofclaim 14. Advantageous further developments of the invention are givenin the dependent claims.

It is characteristic for the inventive adjustment device that the driveunit has a means for the articulated, particularly pivotal connection toa vehicle seat component, especially to a side member of a seat baseframe. That means is adapted so that it guarantees an optimalarrangement of the adjustment device at the vehicle seat component, andalso guarantees a secure connection to the drive unit. Through the useof a means adapted to the drive unit and the intended vehicle seatcomponent, the adjustment device can be optimally fastened to thevehicle seat component. The possibility to design the means consideringonly the general conditions determined by the drive unit and the vehicleseat component guarantees a secure arrangement of the adjustment deviceat a vehicle seat component in a particularly reliable, cost-effectiveand simple manner. Thus, the means offers a simple possibility to mountthe adjustment device at the vehicle seat component in the desiredmanner, without requiring extensive adaptation of the adjustment deviceor of the vehicle seat component for this purpose.

The design of the means can, in principle, be selected freely. Thus, itcan also be formed integrally together with a housing of the drive unit,for example. According to a particularly advantageous design of theinvention, however, the drive unit comprises a detachably connectedretaining element, which is designed for the articulated, especiallypivotal attachment at a vehicle seat component, especially a side memberof a seat base frame. According to this further development of theinvention the retaining element, which can be detachably connected tothe drive unit, forms the means for the articulated, particularlypivotal connection of the adjustment device to the vehicle seatcomponent. The use of such a retaining element makes it possible todesign this element to be specific to vehicle seat components and driveunits. Thus, by means of the design of the retaining element, forexample, the possibility exists, using appropriately designed retainingelements, to dispose a standardized drive unit at various vehicle seatcomponents without requiring extensive transformation measures of theadjustment device for this purpose. It is only necessary to adapt thevehicle seat side of the retaining element, but not the drive unit side.The retaining element forms an adapter which in principle enablescost-effective disposition of various adjustment devices at variousmotor vehicle seats. Also, it is in fact possible to connect differentadjustment devices to a vehicle seat component solely by the use ofsuitable retaining elements such that overall the field of applicationsare particularly increased by the use of a detachably connectedretaining element without this leading to significant increases in cost.Also, in the case of a possibly required exchange, the detachableconnection of the retaining element to the drive unit enables a quickexchange of the adjustment device without extensive assembly work.

The design of the retaining element can in principle be freely selected,such that it can be connected to the vehicle seat component in anarticulated manner. Thus, the retaining element can be provided with apin or a bolt having a threaded section, for example, which extendsthrough an opening at the vehicle seat component, and thereby makes itpossible to attach the adjustment device. However, according to anadvantageous design of the invention, the retaining element comprises abore, especially threaded bore, for receiving a bearing bolt that can bedisposed so as to rotate at a vehicle seat component. This design of theinvention allows a particularly simple and cost-effective production ofthe retaining element, which for the articulated disposition must beprovided only with the bore adapted to a bearing bolt. If necessary, thebore can also have a thread in order to allow a simple releasablefastening of the retaining element to the vehicle seat component,wherein, if necessary, the articulated connection is produced viamounting the bearing bolt with respect to the vehicle seat component.

As already stated at the beginning, it is essential for the function ofthe adjustment device that this is reliably fastened at the vehicle seatcomponent in order to offer sufficient support of the adjusting element.At the same time, however, pivotability must be given so that a reliablepositioning of the vehicle seat structure to be adjusted can be attainedvia the adjusting element, which is adjustable in its longitudinaldirection, and thus, via a distance change of its first end to theadjustment device creating a position change of the vehicle seatstructure to be adjusted. To increase the functional reliability,according to a further development of the invention the retainingelement comprises a stop body that can be brought into contact with thevehicle seat component. The contact surface of the retaining elementwith the vehicle seat component can be determined by means of the stopbody, so that malfunctions, for example a jamming of the adjustmentdevice at the vehicle seat component, are prevented in a particularmanner. Also, by means of the design of the stop body, a predeterminedsupport of the adjustment device at the vehicle seat component can beattained. The arrangement of the stop body at the retaining element canin principle be selected freely, wherein the use of multiple stop bodiesdisposed at a distance to each other is also possible in order to attaingood support in the case of simultaneous reduced contact surface.

According to a particularly advantageous design of the invention, thestop body is disposed, however, coaxially to the bore. A correspondingarrangement of the stop body in the area of the bores provided for theconnection guarantees that the retaining element comes into contact withthe stop body in the area at the vehicle seat component, via which theadjustment device abuts with the highest pressing forces at the vehicleseat component through the bearing bolt used. Distortion within theretaining element can be especially effectively avoided through thisdesign of the invention.

The concrete design of the stop body can, as already stated above, inprinciple be selected freely, and can be designed corresponding to therespectively anticipated loads. Moreover, the possibility exists to formthe stop body from a separate material and to connect it to theretaining element. According to a particularly advantageous design ofthe invention, the stop body is, however, formed integrally with theretaining element. In this design, through suitable production methodsthe retaining element is formed in an area such that in the mountedstate it comprises a defined stop surface with the vehicle seatcomponent. According to this further development of the invention, timeand cost intensive fastening methods for disposing a separate stop bodycan be avoided so that the adjustment device can be producedparticularly cost-effectively. For the supplemental improvement of thefunctional reliability, according to a further development of theinvention, the stop body can have a slide coating by means of which thefriction existing during operation between the vehicle seat componentand the stop body can additionally be minimized, and thus, wear can beprevented.

The concrete design of the retaining element such that this is connectedto the drive unit and makes possible an attachment of the adjustmentdevice to a vehicle seat component, can be freely selected correspondingto the constructive specifications due to the drive unit and due to thevehicle seat component. However, according to a particularlyadvantageous design of the invention, the retaining element isconstructed such that it encompasses the drive unit at least partiallyin a U-shape manner. This design of the invention guarantees that theretaining element experiences good support at the drive unit so that theadjustment device has a particularly high functional reliability. Theconnection between the retaining element and the drive unit occurs herepreferably via the free limbs of the U-shaped retaining element so thatthe latter is secured in a particularly reliable manner in its positionat the drive unit. A connecting bolt extends, particularlyadvantageously, through suitable openings in the free limbs of theU-shaped retaining element, and also through the drive unit.

A displaceability of the adjusting element in its longitudinal directionby the drive unit is essential for the function of the adjustment devicein order to achieve an adjustment of a vehicle seat structure connectedto the adjusting element. A free axial shiftability of the adjustingelement is therefore essential for the function of the adjusting devicedisposed at a vehicle seat component. According to a particularlyadvantageous design of the invention, the retaining element comprises athrough opening for receiving the adjusting element in a displaceablemanner. This design of the retaining element allows, in connection withthe drive unit, a particularly compact design and furthermore permits,if necessary, the use of the retaining element for supporting theadjusting element, wherein for this purpose the through openings aredesigned correspondingly with appropriate bearing bolts, for example. Inits simplest design, however, the through openings are constructed sothat they only permit a free shiftability of the adjusting element withrespect to the retaining element.

The fundamental alignment of the support axes and movement axes can beselected freely. However, according to a particularly advantageousdesign of the invention, the bore for receiving the bearing bolt and theadjusting element are disposed so that their longitudinal axes progressessentially at right angles to each other and in a common plane. Throughthis design of the invention, damaging transverse forces and torquesacting on the adjusting element are substantially avoided so that thefunctional reliability can be additionally increased. In addition, thisdesign of the invention is characterized by a particularly compactconstruction.

The design of the drive unit, such that it causes a shift of theadjusting element, in principle can be freely selectable. Thus, ahydraulic or pneumatic drive unit, for example, can be used which offersthe possibility of longitudinal shifting of the adjusting element. Theuse of a piston-cylinder unit or similar is conceivable, wherein anadjustment of the connected vehicle seat structure is possible via theposition of the piston with respect to the cylinder. However, accordingto a particularly advantageous design of the invention, the drive unitcomprises a motor unit and a transmission unit, wherein the adjustingelement is in engagement with the transmission unit. According to thisdesign of the invention, wherein the motor unit is formed preferably byan electric motor drive, a particularly simple, cost-effective andreliable adjustment device can be constructed. The use of a transmissionunit enables on the one hand a relatively free arrangement of the driveunit with respect to the adjusting element and on the other hand, ifdesired, a transmission of the drive moment which is provided by thedrive unit.

According to a particularly advantageous design of the invention, themotor unit is coupled via a worm disposed on an output shaft to a wormgear mounted so as to rotate in a transmission housing, wherein the wormgear is constructed as a spindle nut to drive a spindle disposed axiallyin the worm gear. This design of the invention is characterized by itsparticularly compact construction, wherein simultaneously reliableadjustment of the adjusting element formed as a spindle is guaranteed.Furthermore, the spindle is characterized by its suitability, accordingto a further development of the invention, to be designed self-lockingso that, if necessary, no further measures are necessary for securingthe position of the vehicle seat structure adjusted by the adjustmentdevice.

The design of the spindle is in principle freely selectable, wherein thepreviously described design that it is self-locking, enables simplesecuring of the position of the adjusted location of vehicle seatstructure to be adjusted. Furthermore, according to a particularlyadvantageous design of the invention, the spindle at the first endcomprises a connecting link for articulated connection to a lever and astop element at its second end, opposite to the first end. Theconnecting link permits a particularly simple attachment to the vehicleseat structure to be adjusted, and the stop element guarantees that thespindle in each case remains in engagement with the transmission unit.In this respect, the functional reliability of the adjustment deviceaccording to the invention can be additionally increased.

The motor vehicle seat according to the invention, having a seat baseframe and an adjustable assembly with respect to the seat base frame, ischaracterized in that an articulated, in particular pivotal, adjustmentdevice according to one or more of the claims 1 to 13 is disposed at theseat base frame, in particular at a side member. A correspondinglydesigned motor vehicle seat can be disposed in a particularly simple andcost-effective manner, wherein the use of a retaining element permits agood adaptation of the adjustment device to be used to the motor vehicleseat, wherein furthermore, due to the retaining element a plurality ofdifferent adjustment devices can be disposed at the seat base frame, andthereby allow an optimal design of the motor vehicle seat.

Particularly advantageously, the adjustment device is connected to theadjustment device in an articulated manner via a bearing bushingdisposed at a seat base frame, whereby the functional reliability of themotor vehicle seat can be increased additionally, and malfunctions areexcluded to the greatest extent possible.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

An exemplary embodiment of the invention is explained in the followingin more detail with reference to the drawings. The drawings show:

FIG. 1 a perspective view of an adjustment device in a partiallydisassembled state,

FIG. 2 a side view of a portion of a motor vehicle seat having anadjustment device disposed at a side surface of a seat base frame, and

FIG. 3 a view of the adjustment device from FIG. 1 in an assembled stateon a side member, partially represented in section.

DETAILED DESCRIPTION OF THE INVENTION

The adjustment device 1 represented in FIG. 1 comprises a drive unit 3and a retaining element 4, detachably connected to the drive unit 3, bymeans of which the adjustment device 1 is fastened to a vehicle seatcomponent, here at a side member 18 of a seat base frame 30, as shown inFIGS. 2 and 3. The drive unit 3 of the adjustment device 1 comprises amotor unit 5 and a transmission unit 6 connected to the motor unit 5,wherein an adjusting element constructed as a spindle 2 can be adjustedin its longitudinal direction at the transmission unit 6.

For transmitting a rotational movement of an output shaft 8 of the motorunit 5 to the spindle 2, the transmission unit 6 comprises a worm gear9, disposed so as to rotate in a transmission housing 10, that on theoutside engages with a worm 7 disposed on an output shaft 8 of the motorunit 5, so that rotational movements of the output shaft 8 are convertedinto a rotational movement of the worm gear 9. The worm gear 9 isconstructed as a spindle nut for driving the spindle 2, so thatrotational movements of the worm gear 9 in a longitudinal directionguide the spindle 2 disposed axially at the worm gear 9. The adjustmentdevice of the spindle 2 is dependent on the rotational direction of theoutput shaft 8.

The spindle 2 itself comprises a connecting link 26 at a first end withwhich it is connected in an articulated manner to a vehicle seatstructure 20 to be adjusted, wherein security against rotating thespindle 2 is also created by means of the produced connection. At itsend opposite to the first end, the spindle 2 further comprises a stopelement 25, which limits the longitudinal motion of the spindle 2.

The connection of the spindle 2 via the connecting link 26 to a vehicleseat structure 20 to be adjusted can in principle occur in any manner.However, in the example embodiment shown in FIG. 2, the spindle 2 isconnected via the connecting link 26 to a lever 19 which is disposed soas to rotate at a side member 18 of a seat base frame 30, wherein thelever 19 in turn at its end opposite the spindle 2 is connected in anarticulated manner to a seating surface 20, so that an adjustment ofthis vehicle seat structure is possible due to the adjustment device 1.

In the present exemplary embodiment, the side surface 18 of the seatbase frame 30 is connected to an upper rail 22 of a rail pair 21,wherein the slidability of the upper rail 22 with respect to a lowerrail 23 allows a longitudinal adjustability of the motor vehicle seat28. Neither the arrangement of the adjustment device 1 at a side surface18, nor the arrangement of a side surface 18 at an upper rail 23 ismandatory. Thus, the side member 18 can also be a component of the seatbase frame 30 in another manner, or the adjustment device 1 can bedisposed at another location.

A retaining element 4 that is a component of the adjustment device 1,serves for the arrangement of the drive unit 3, composed of the motorunit 5, transmission unit 6 and the adjusting element 2, at the sidesurface 18 of the seat base frame 30. The retaining element 4 comprisesa U-shaped form, wherein the distance between the free limbs of theretaining element 4 is selected so that the retaining element 4encompasses the transmission housing 10. Through openings 12 disposed inthe free limbs permit the passage of the spindle 2 through the retainingelement 4. Fastening openings 13 a, 13 b also disposed in the freelimbs, permit the retaining element 4 to be fastened to the transmissionhousing 10, for which a fastening screw 27 extends through both thefastening openings 13 a, 13 b as well as through a through bore 14 inthe transmission housing 10 so that the retaining element 4 isdetachably disposed at the transmission housing 10.

On the outside at its base area facing the side member 18, the retainingelement 4 comprises a threaded bore 11 coaxially to which a projectingstop body 15 is disposed that in the assembled state abuts at the sidesurface 18 of the seat base frame 30. A bearing bolt 16, serving for thepivotal connection of the adjustment device 1, can be screwed to anend-side threaded section in the threaded bore 11, and with a bearingsection 17 is disposed in the assembled state in the area of an opening24 of the side surface 18, wherein for improving the pivotal mounting abearing bushing 29 is installed in the opening 24. This arrangement ofthe adjustment device 1 using the retaining element 4 guarantees aparticularly trouble-free operation in the case of an adjustment of theseating surface 20 with respect to the seat base frame 30.

1. An adjustment device for a motor vehicle seat, having an adjustingelement adjustably disposed in its longitudinal direction and in thearea of one end, connectable in an articulated manner to a vehicle seatstructure, and a drive unit driving the adjusting element, comprising adetachably connected retaining element for pivotal connection of thedrive unit to a vehicle seat component, wherein the retaining elementcomprises a through opening for receiving the adjusting element in adisplaceable manner.
 2. The adjustment device according to claim 1,wherein the retaining element comprises a bore, in particular a threadedbore for receiving a bearing bolt that can be disposed so as to rotateat a vehicle seat component.
 3. The adjustment device according to claim2, wherein the bore and the adjusting element are disposed so that theirlongitudinal axes run essentially at right angles to each other and in acommon plane.
 4. The adjustment device according to claim 1, wherein theretaining element comprises a stop body that can be brought into contactwith the vehicle seat component.
 5. The adjustment device according toclaim 4, wherein the stop body is disposed coaxially to the bore.
 6. Theadjustment device according to claim 4, wherein the stop body is formedintegrally with the retaining element.
 7. The adjustment deviceaccording to claim 4, wherein the stop body comprises a slide coating.8. The adjustment device according to claim 1, wherein the retainingelement is constructed such that it encompasses the drive unit at leastpartially in a U-shape.
 9. The adjustment device according to claim 1,wherein the drive unit comprises a motor unit and a transmission unit,wherein the adjusting element is in engagement with the transmissionunit.
 10. The adjustment device according to claim 9, wherein the motorunit is coupled via a worm disposed on an output shaft to a worm gearmounted so as to rotate in a transmission housing, wherein the worm gearis constructed as a spindle nut for driving a spindle disposed axiallyin the worm gear.
 11. The adjustment device according to claim 10,wherein the spindle comprises a connecting link at the first end for thearticulated connection to a lever, and a stop element at its second endopposite to the first end.
 12. A motor vehicle seat having a seat baseframe and an assembly adjustable with respect to the seat base frame,wherein the adjustment device according to claim 1 is disposed in apivotal manner at the seat base frame.
 13. The motor vehicle seataccording to claim 12, wherein the adjustment device is mounted in anarticulated manner via a bearing bushing disposed in an opening of thevehicle seat component.
 14. The motor vehicle seat according to claim13, wherein the vehicle seat component is a side member.